Related Experiment Video
Updated: Apr 27, 2026

Comparing the Effects of Electronic Cigarette Vapor and Cigarette Smoke in a Novel In Vivo Exposure System
Published on: May 24, 2017
Carbon monoxide and respiratory symptoms in young adult passive smokers: a pilot study comparing waterpipe to
Rouba Karen Zeidan1, Samar Rachidi, Sanaa Awada
1Faculty of Pharmacy, Laboratory of Clinical and Epidemiological Research, Lebanese University, Hadath, Lebanon.
Objectives:
Studies have correlated second hand smoke (SHS) with many diseases, especially respiratory effects. The goal of this study was to measure the impact of SHS on the respiratory symptoms and exhaled carbon monoxide.
Material And Methods:
The study population consisted of 50 young workers in restaurants serving waterpipes, 48 university students who sit frequently in the university cafeteria where cigarette smoking is allowed and 49 university students spending time in places where smoking is not allowed. Subjects completed questionnaires on socio-demographic characteristics, respiratory symptoms and exposure to SHS. Exhaled carbon monoxide levels were measured. ANOVA and Chi-square tests were used when applicable as well as linear and logistic regression analysis.
Results:
Exposure to cigarette smoke in university (adjusted odds ratio (ORa) = 6.06) and occupational exposure to waterpipe smoke (ORa = 7.08) were predictors of chronic cough. Being married (ORa = 6.40), living near a heavy traffic road (ORa = 9.49) or near a local power generator (ORa = 7.54) appeared responsible for chronic sputum production. Moreover, predictors of chronic allergies were: being male (ORa = 7.81), living near a local power generator (ORa = 5.52) and having a family history of chronic respiratory diseases (ORa = 17.01). Carbon monoxide levels were augmented by the number of weekly hours of occupational exposure to waterpipe smoke (β = 1.46) and the number of daily hours of exposure to cigarette smoke (β = 1.14).
Conclusions:
In summary, young non-smoker subjects demonstrated more chronic cough and elevated carbon monoxide levels when exposed to SHS while the effect of waterpipe was even more evident.
Related Concept Videos
Chronic Obstructive Pulmonary Disease III: Chronic Bronchitis Features
Chronic Obstructive Pulmonary Disease I: Introduction
Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
Chronic Obstructive Pulmonary Disease-I: Introduction
COPD: Pathogenesis and Clinical Features
The primary cause for the onset of COPD is cigarette smoking and exposure to air pollution. These hazardous factors initiate a chain reaction within the lungs, resulting in chronic inflammation, damage to the airways, and a...
Chronic Obstructive Pulmonary Disease
Smoking is a primary risk factor for COPD, with over 80% of patients having a history of it. Patients typically experience progressive dyspnea or labored breathing, frequent coughing, and recurrent pulmonary infections. Many eventually succumb to respiratory failure, characterized by...

